The present invention relates to a prediction coding system which permits high-efficiency coding of a picture signal such as of commercial television or video telephone through utilization of the high correlation present between adjacent picture elements in a picture.
In the existing standard television a picture is made up of frames which are transmitted by steps of thirty in a second, and each frame consists of two continuous fields because of interlaced scanning every other scanning line. Elements which make up the picture are called "picture elements" but, in this specification, as digital processing is borne in mind, one sample after being subjected to sampling will hereinafter be referred to as a picture element. Accordingly, in this case, the position of each picture element in the frame depends on the sampling frequency used for digitizing a signal.
The background of the present invention will be clearly understood from the following detailed description.